Segments in – segments out, or can translations sound natural?

What are essential attributes of a successful translation project?

Anyone would mention client instructions, TM and glossary. The quality and success of a project is often measured as the degree to which those three were adhered. And indeed translators like when the TM is clean and the glossary is unambiguous, and they totally love when client instructions say: your translation should read as if it was originally written in your language. We are all artists, and we do appreciate when customers want us to show how good we are in our native language.